The goals of this project are to address the fundamental limitations of magnetic resonance imaging (MRI) in evaluating patients with metallic implants. We will develop a complete 3D distortion- corrected imaging and reconstruction technique that provides diagnostic images without metal-induced artifacts. We will also provide different contrast mechanisms for imaging near metal. All the techniques will be validated in a cadaveric model and in vivo in subjects with spinal implants. Relevance: MRI is widely regarded as the best imaging modality for orthopedic conditions such as osteomyelitis, a vascular necrosis, tendon or ligamentous injury, bone or soft tissue lesions, spinal nerve root compression, and spinal stenosis. Unfortunately, in patients with metallic implants, MRI is hampered by metal-induced artifacts (e.g., severe signal loss, distortions), and failure of fat suppression at the locations near the implants. These are precisely the locations where post-surgical complications are likely to occur, and thus where accurate imaging could have the greatest clinical impact. Approach: This project addresses these technical challenges of performing MRI near metallic implants. Our approach is to develop new pulse sequences that require no additional hardware and can be utilized on the large installed base of 1.5T MRI systems. Specifically, we aim to (1) develop 3D imaging methods to eliminate all metal-induced artifacts, (2) develop more robust fat suppression in the presence of metal, and (3) evaluate our imaging methods in a cadaver study, followed by a study of 12 patients who have previously received spinal implants. At the end of the funding period, we will have developed methods that provide distortion- free images and robust fat suppression near metallic implants. The success of this project will improve the diagnosis and treatment of millions of patients. PUBLIC HEALTH RELEVANCE: Metallic implants are being used increasingly to treat chronic and acute injuries to the spine, hip and knee. Magnetic resonance imaging (MRI) is commonly used for evaluating orthopedic conditions, but fails near metallic implants due to severe magnetic field inhomogeneities caused by metal. This research project will develop complete 3D correction of metal-induced distortions to radically improve MRI near implants.